There have been hitherto proposed methods for producing a gas barrier film characterized by having excellent gas barrier properties and also requiring a short production time (see, for example, Patent Document 1), together with substitutes for glass substrates for organic EL elements.
More specifically, the method for producing a gas barrier film described in Patent Document 1 is a method for producing a gas barrier film, characterized in that a perhydropolysilazane-containing liquid is applied on at least one surface of a base material, a polysilazane film formed by heating and drying the liquid is subjected to a normal pressure plasma treatment or a vacuum plasma treatment, and thereby a gas barrier film having a water vapor transmission rate (WVTR), which is an index for water vapor barrier properties, of 1 g/(m2·day) or less and having a thickness of 0.01 μm to 5 μm is obtained.
Furthermore, there has been proposed a method for producing a gas barrier film including a silicon oxide thin film having very high gas barrier properties so that the gas barrier film can be applied to a resin base material for organic photoelectric conversion elements (see, for example, Patent Document 2).
More specifically, the method for producing a gas barrier film described in Patent Document 2 is a method for producing a gas barrier film, characterized in that a silicon-containing liquid is applied on at least one surface of a base material and dried at 20° C. to 120° C. to form a silicon thin film, and then a silicon oxide thin film is formed on the silicon thin film by a plasma CVD method using an organosilicon compound and a reactive gas containing oxygen.
Furthermore, a gas barrier film including a carbon-containing silicon oxide film, which exhibits excellent transparency without having decreased gas barrier properties, has been proposed (see, for example, Patent Document 3).
More specifically, the gas barrier film described in Patent Document 3 is a gas barrier film characterized in that a carbon-containing silicon oxide film having a film thickness of 5 nm to 300 nm is formed on at least one surface of a base material film, and the composition ratio (C/Si) of carbon atoms (C) and silicon atoms (Si) in the carbon-containing silicon oxide film is within the range of above 0 and equal to 1 or less, while the degree of coloration (YI) is within the range of 1.0 to 5.0.
Furthermore, in order to be able to provide a gas barrier film having excellent transmittance and color tinge, there have been proposed a gas barrier film having regions A, B and C, in which the silicon content, the oxygen content, and the nitrogen content are different, and a method for production thereof (see, for example, Patent Document 4).
More specifically, the gas barrier film described in Patent Document 4 is a gas barrier film which is configured to include a region A in which the oxygen content is larger than the nitrogen content; a region B in which the nitrogen content is larger than the oxygen content, and to include, between these region A and region B, a region C in which the oxygen content of the region A gradually decreases, while the nitrogen content gradually increases toward the region B. This gas barrier film is a gas barrier film having the various regions disposed on a base material film in the order of regions ACB, regions BCA, or regions ACBCA, toward the surface.